Businesses, governments, and individuals depend more and more on the data security and privacy protection in cyber systems. As data collection becomes broader and easier through automated data collection, sensors, and the IoT, protecting the data is becoming more of a focus. The concept of "big data" just increases the focus. Many of the contributions to this focus is on maintaining data security and privacy in the process, storage, transmission, and decision-making. However, there can be a question, what would be the situation if low-quality, untrustworthy, meaningless, or undependable data are collected at the time of acquisition, and we apply various strong security protocols to process, store, and transmit the data and make decisions for various cyber applications. Also, what would be the situation when existing privacy-preserving protocols for communication and decision-making can be effective but to what value if the data being project are themselves suspect due to attacks on the privacy at the data gathering process. In this talk, I will highlight these situations and show how untrustworthy concerns may appear during the data collection. I will then discuss challenges and potential solutions for the trustworthy data collection.